Emerging medical procedural guidance systems utilize a combination of ultrasound and magnetic technologies to visualize a patient's sub-dermal anatomy and to provide guidance for positioning an invasive medical device, for example, a needle, a stylet or a guidewire. The combination of ultrasound and magnetic methods allows for estimation of the position of the insertion device relative to the patient's anatomy, and thereby improves the likelihood of successfully accessing the vascular and completing the invasive procedure.
Ultrasound and magnetic procedural guidance system technology relies on the invasive device having a magnetic field source. One way to magnetize a portion of the invasive device prior to insertion is by using an externally applied magnetic field. For systems that apply an external magnetic field, the portion of the invasive device that is targeted for magnetization is the metal cannula of the invasive device, for example, the cannula of a needle. For this type of system, a separate device with integrated magnets is used to actively magnetize the needle just prior to the insertion procedure.
Systems that require the user to actively magnetize the metal cannula have certain limitations and inherent risks as this approach does not guarantee consistent magnetization given the reliance of the user to place the needle into the needle magnetizer and the variation of how this is done (i.e. depth, speed, centering, etc.).
Thus, there is a need for a system that passively and consistently magnetizes the needle while reducing or eliminating risks, such as needle tip damage and needle contamination.